exam 3 review Flashcards
what is metabolism
the entire set of enzyme-catalyzed transformations of organic molecules in living cells; the sum of anabolism and catabolism
what is anabolism
the phase of metabolism concerned with the energy-requiring biosynthesis of cell components from smaller precursors
what is catabolism
the phase of metabolism concerned with the energy-yielding degradation of nutrient molecules.
where does glycolysis occur
in the cytoplasm
where does pyruvate oxidation, and the citirc acid cycle occur
in the mitochondrial matrix
where does electron transport and ATP synthesis (creation of CO2 and H2O as well) occur
in the inner mitochondrial membrane
in the overall reactions of glycolysis, what do we start with?
1 glucose, 2 NAD+, 2 ADP, 2Pi
in the overall reactions of glycolysis, what do we end with?
2 pyruvate, 2 NADH, 2 ATP, 2 H20, 2H+
Can NAD+ be transferred to the electron transport chain?
yes, 4 electrons are passed to NAD+ which when it becomes NADH make it transferrable.
step 1 of glycolysis
Glucose is phophorylated with a kinase mkaing glucose 6-phosphate; taking energy from ATP and transferring it to glucose.
step 2 of glycolysis
An isomerase swaps the oxygen and hydroxyl groups to rearrange the molecule.
step 3 of glycolysis
phosphorylation of fructose-6 phosphate catalyzed by phosphofructokinase. an ATP donates a phosphate group producing fructose-1, 6-bisphosphate and ADP as products
step 4 of glycolysis
Lysis of glycolysis where an enzyme is enacted to split the sugar into 2 3-carbom molecules each with a phosphate group
step 5 of glycolysis
triosephosphate isomerase interconverts he molecules dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (GAP) removing glyceraldehyde completely
step 6 of glycolysis
2 seperate rxns occur:
1. glyceraldehyde-3-phosphate is oxidized by the coenzyme (NAD)
2. the molecule is phosphorylated by the addition of a free phosphate group.
step 7 of glycolysis
we see payoff with the production of 2 ATP. Phosphoglycerate kinase transfers a phosphate group from 1,3-bisphosphoglycerate to ADP to form ATP and 3-phosphoglycerate.
step 8 of glycolysis
The enzyme phosphoglycero mutase relocates the P from 3- phosphoglycerate from the 3rd carbon to the 2nd carbon to form 2-phosphoglycerate. rearrangement of phophate groups.
step 9 of glycolysis
The enzyme enolase removes a molecule of water from 2-phosphoglycerate to form phosphoenolpyruvic acid (PEP). Enolase works by removing a water group, or dehydrating the 2 phosphoglycerate.
step 10 of glycolysis
The enzyme pyruvate kinase transfers a Phosphate from phosphoenolpyruvate (PEP) to ADP to form pyruvic acid and ATP Result in step 10.
Which steps of glycolysis have large -∆ G and what does that mean?
Steps 1, 3, and 10 have large -∆ G’s meaning that these steps are essentially irreversible.
what step of glycolysis is oxidation?
step 6, coenzyme NAD+ turns into NADH
which two steps of glycolysis have substrate level phosphorylation?
Steps 7 and 10 where the first and second ATP forming reactions occur
what are the pathways pyruvate (product of glycolysis) can take?
- can be completely oxidized into 2 CO2 aerobically and generate more ATP
- can be processed anaerobically to lactate or ethanol
